Novel solid state air pump for forced convection electronics cooling

Increasing functional densities and clock frequencies continue to drive electronic device power dissipation densities upwards. At the same time, reducing electronic package size has diminished the ability to incorporate traditional heat dissipation devices by virtue of their physical size. As a result, there is a need to develop new compact methods for heat dissipation, complementary to modern packaging developments. The paper details the design, evaluation, and application of a 35 mum³ valve-less diaphragm micro-pump (Staley, T. et al., 2007) for forced convection within a small volume. The prototype device provides reliable and cost effective heat dissipation with time averaged air velocities in excess of 2.5 m/s. Demonstrations show strong potential for drastically reducing the thermal resistance of semiconductor packages. The device consists of a solid state back to back diffuser assembly driven by piezoelectric crystals. The focus of the paper is on the experimental study of the design, fabrication and test of the prototype diffuser based piezoelectric diaphragm pump for semiconductor spot cooling applications. Test data details the volumetric flow rates and time averaged air velocities generated by the device. In addition, a full performance simulation by computational fluid dynamics is presented to complement the experimental performance data. Prototype problems are identified, with solutions and continuing development directions proposed.